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Porphyria, ALA-D

It is possible that the main title of the report Porphyria, ALA-D is not the name you expected. Please check the synonyms listing to find the alternate name(s) and disorder subdivision(s) covered by this report.


  • ADP
  • ALA-dehydratase deficient porphyria
  • ALAD deficiency
  • Doss porphyria
  • porphyria of Doss
  • delta-aminolevulinate dehydratase deficiency

Disorder Subdivisions

  • None

General Discussion

ALAD porphyria is an extremely rare genetic metabolic disease characterized by almost complete deficiency of the enzyme delta-aminolevulinic acid dehydratase. Deficiency of this enzyme leads to the accumulation of the porphyrin precursor delta-aminolevulinic acid, which can potentially result in a variety of symptoms. Specific symptoms can vary greatly from one person to another, but usually affect the neurological and gastrointestinal systems. This disease is inherited as an autosomal recessive disorder.

ALAD porphyria is one of a group of disorders known as the porphyrias. The porphyrias are characterized by abnormally high levels of porphyrins and porphyrin precursors in the body due to deficiencies of certain enzymes essential to the creation (synthesis) of heme, a part of hemoglobin. There are at least seven types of porphyria. The symptoms associated with the various types of porphyria differ. It is important to note that people who have one type of porphyria do not develop any of the other types. Porphyrias are generally classified into two groups: the "hepatic" and "erythropoietic" types. Porphyrins and related substances originate in excess amounts from the liver in the hepatic types, and mostly from the bone marrow in the erythropoietic types. ALAD porphyria is a hepatic form of porphyria.


CLIMB (Children Living with Inherited Metabolic Diseases)
Climb Building
176 Nantwich Road
Crewe, CW2 6BG
United Kingdom
Tel: 4408452412173
Fax: 4408452412174

American Porphyria Foundation
4900 Woodway, Suite 780
Houston, TX 77056-1837
Tel: (713)266-9617
Fax: (713)840-9552
Tel: (866)273-3635

NIH/National Institute of Diabetes, Digestive & Kidney Diseases
Office of Communications & Public Liaison
Bldg 31, Rm 9A06
31 Center Drive, MSC 2560
Bethesda, MD 20892-2560
Tel: (301)496-3583

MedicAlert Foundation International
2323 Colorado Avenue
Turlock, CA 95382
Tel: (209)669-2401
Fax: (209)669-2456
Tel: (888)633-4298

British Porphyria Association
136 Devonshire Rd
Durham City, DH1 2BL
United Kingdom
Tel: 01474369231

Genetic and Rare Diseases (GARD) Information Center
PO Box 8126
Gaithersburg, MD 20898-8126
Tel: (301)251-4925
Fax: (301)251-4911
Tel: (888)205-2311
TDD: (888)205-3223

For a Complete Report:

This is an abstract of a report from the National Organization for Rare Disorders (NORD). A copy of the complete report can be downloaded free from the NORD website for registered users. The complete report contains additional information including symptoms, causes, affected population, related disorders, standard and investigational therapies (if available), and references from medical literature. For a full-text version of this topic, go to and click on Rare Disease Database under "Rare Disease Information".

The information provided in this report is not intended for diagnostic purposes. It is provided for informational purposes only. NORD recommends that affected individuals seek the advice or counsel of their own personal physicians.

It is possible that the title of this topic is not the name you selected. Please check the Synonyms listing to find the alternate name(s) and Disorder Subdivision(s) covered by this report

This disease entry is based upon medical information available through the date at the end of the topic. Since NORD's resources are limited, it is not possible to keep every entry in the Rare Disease Database completely current and accurate. Please check with the agencies listed in the Resources section for the most current information about this disorder.

For additional information and assistance about rare disorders, please contact the National Organization for Rare Disorders at P.O. Box 1968, Danbury, CT 06813-1968; phone (203) 744-0100; web site or email

Last Updated: 9/7/2010
Copyright 1987, 1988, 1990, 1997, 2001, 2010 National Organization for Rare Disorders, Inc.

WebMD Medical Reference from the National Organization for Rare Disorders

Last Updated: May 28, 2015
This information is not intended to replace the advice of a doctor. Healthwise disclaims any liability for the decisions you make based on this information.

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